1. Field of the Invention
This invention relates to a display panel utilizing gas discharge, particularly to a new large size panel structure of the surface discharge type, the monolithic type or the planar type gas discharge panel.
2. Description of the Prior Art
The surface discharge type, monolithic type or planar type panel is employed as a kind of gas discharge panel. The gas discharge panel of this type, as is well known, for example, from the U.S. Pat. No. 3,646,384 issued Feb. 29, 1972 to Frank M. Lay, provides the characteristic that the X electrodes and Y electrodes are laid only on one substrate of a pair of substrates arranged face-to-face via the gas filled space, and that the horizontal discharge is generated along the substrate surface in the area near to the intersecting points of the electrodes. Such a structure provides the advantages that the requirement of accuracy for the gap between paired substrates (discharge gap) is drastically alleviated as compared with the panel having the face-to-face electrode structure, and moreover conversion of display color and multi-coloration can be realized easily by providing the ultra-violet rays activation type fluouresecent material at the internal side of a covering substrate. Recently, it has become desirable for the display device utilizing such a gas discharge panel to display large size images and figures and a large amount of characters and therefore the pertinent panel must be increased in size. On the occasion of producing such a large size display panel, the surface discharge panel provides the advantage, as explained above, that panels having uniform discharge characteristics can easily be obtained depending on the flatness of the glass substrate used because high discharge gap accuracy is not required. But even this surface discharge panel has a problem in that the probability of generating electrode disconnection and termination of electrodes on the substrate becomes high as the panel size is enlarged and resultingly the number of electrodes is increased. As a result, the yield of panel production is drastically lowered. In addition, such a panel has a problem in that a large scale facility is required for formation of electrodes.
On the other hand, an ordinary gas discharge panel of the face-to-face electrode type, as shown in U.S. Pat. No. 3,886,390 and Japanese Examined Patent Publication No. 55-10197 has a large size display surface by combining a plurality of small size discrete panels, each being completed assembly. However, such a well known panel having a large size display structure cannot be free from the generation of a discontinuous display at the joint areas between adjacent panels.